House Minority Leader Nancy Pelosi (D-Calif.) cast doubt on Friday on the idea that allowing the top marginal tax rate to rise merely from 35 to 37 percent would raise sufficient revenue to significantly address the nation's debt problem.

The top rate, on income over $250,000, now stands at 35 percent and will rise automatically to 39.6 percent in January without congressional action. Democrats have insisted that the top rate increase as part of a deal to avert the year-end fiscal cliff. President Obama has signaled that he could compromise on a number somewhere between the two -- and there has been some discussion on the Hill about looking at a deal around 37 percent.

Asked if that would produce enough revenue, Pelosi told reporters, "No. I don’t know that. That’s why we should be here to have kind of review of the facts."

She said Democrats' goal was to raise enough revenue to help address the problem, without having to ask more of -ncome taxpayers.

"What we want to do is protect the middle class. It’s not about the rate. It’s about the money," she said.

But she added there could be a solution that also looked at raising the tax rate applied to capital gains and dividends.

Pelosi also kept up pressure Friday on Republicans to agree to extend tax cuts first enacted under President George W. Bush on income less than $250,000 and allow rates to rise on the nation's wealthiest households before the year-end fiscal cliff hits.

"This is a moment of truth. The clock is ticking. Christmas is coming," she said.